3. CAPITULO III: MARCO TEORICO Y CONCEPTUAL
3.5. Métricas de valorización
3.5.2. Métricas de Múltiplos Comparables o Ratios
This section outlines the role of Health Agencies in drinking water safety and the acceptable actions Health Agencies in their dealing with unacceptable bacteriological results, and defines the communication protocol between the Provincial Laboratory for Public Health (Microbiology) Health
Agencies. Fact sheets and draft scripts to serve as examples for Health Agencies are also included in case a boil water advisory has to be ordered.
* Information intended for the public and a generic version is
provided on the attached compact-disc for Health Agencies
to reproduce
CHAPTER 6 – COMMUNICATION AND ACTION PROTOCOL
6.1 ROLES AND RESPONSIBILITIES OF REGIONAL, PROVINCIAL AND FEDERAL HEALTH AGENCIES
Regional Health Authorities (RHA) and Health Canada’s Safe Environments Programme and Environmental Health Services within Alberta have a primary role in ensuring the safety of drinking water supply by enforcing legislation, participating in the development of “Guidelines for Canadian Drinking Water Quality” and providing education/advice to the water purveyors and public at large. The legal responsibility of a RHA in ensuring the safety of drinking water lies within the Public Health Act. Section 11 of the Nuisance and General Sanitation Regulation 243/2003 states that:
“…Water must be potable. Where a person provides a source of water that the person intends to be used or realizes or ought to realize will be used by the public for human consumption, the person shall ensure that the water is potable…”
and section 12 states:
“…Where under any law a potable water supply is required to be provided in or at any public place, the owner of the public place shall ensure that the equipment used for the transmission, treatment and storage of the water is maintained in adequate operating condition and in a clean and sanitary condition…”
To achieve this goal, environmental public health officials must cooperate with Alberta Environment and local utilities to ensure that the water delivered to the public is safe for consumption. The importance of water safety is reflected in the “Common Reference System and Operational Standards for Alberta Regional Health Authority Environmental Health Programs,” or commonly referred to as the “Blue Book.” One of the program areas defined as essential is “Safe Drinking Water.” The goal of the program is to reduce the waterborne adverse health effects related to water consumption.
Health Canada in collaboration with Indian and Northern Affairs Canada, helps First Nation communities ensure safe drinking water on their lands. Under the Drinking Water Safety Program of Environmental Health Services, Health Canada works in partnership with the First Nations to monitor drinking water quality in First Nation communities.
Water Quality and Health Bureau of the Safe Environments Program in collaboration with the provincial and territorial governments develops guidelines for new substances and upgrades the existing “Guidelines for Canadian Drinking Water Quality.” These guidelines provide the basic tools to all levels of government across Canada to develop and promulgate stringent drinking water standards specific to their jurisdictional needs.
To meet these objectives, the role of Health Agencies in ensuring the safety of drinking water within Alberta should therefore include prevention, protection, promotion and education:
1. Preventing waterborne outbreaks from occurring by:
• Determining the quantity & quality of source water, types of contaminants such as chemicals, radiological and microbiological and their sources; and
• Working with all levels of government and Utilities to identify critical control points within treatment processes for effective monitoring, control and management including determining treatment efficiency in the removal or inactivation of harmful agents found in source water
2. Protecting the public and minimizing the impact of waterborne outbreaks through:
• Early detection of enteric cases within the community using active monitoring and passive surveillance systems; and
• Effective and timely declaration of water quality advisories such as “Boil Water” or “Do not Drink Water” and the ability to provide complete, and accurate information to the public regarding the water quality status.
3. Act as one of the central resources for health information and promote water safety through:
• Effective partnership, collaboration and cooperation with all levels of government and Utilities in promoting water safety; and
• Provide accurate and timely information to the public on the safety of their water supply
6.2 PROTOCOL FOR FAILED BACTERIOLOGICAL RESULTS IN DRINKING WATER FOR PRIVATE, PUBLIC AND COMMUNAL DRINKING WATER SYSTEMS
Introduction:
It is estimated that over 600,000 Albertans derive their drinking water from supplies and systems that fall outside of the licensing and approvals process of Alberta Environment. Officials who represent the interests of public health, the environment and various levels of government recognize and are concerned about the vulnerabilities that may exist with these supplies and in particular the need for early and effective notification in situations where health may be at risk.
To this end, this protocol is designed to provide a consistent and effective means of addressing public health risks associated with microbiological contamination of private, public and communal drinking water systems.
Microbiological contamination in water supplies:
Testing for bacteria in drinking water is an important monitoring tool for ensuring microbiologically safe drinking water. Evidence of the presence of Total
Coliform/E. coli bacteria may indicate a potential health risk requiring follow-up action.
6.2.1 Roles and Responsibilities
A) Regional Health Authorities and Health Canada
• Monitor submission of water samples and resamples from supplies to ensure compliance and appropriate follow-up as needed,
• Interpret laboratory results and determine when remedial action, including
"Boil Water Advisories/Orders" need to be implemented and rescinded,
• Respond to notification of failed bacteriological results from laboratory, and
• Provide and maintain a current list of emergency contact personnel and their contact numbers to the laboratory.
Note: While it is understood that conditions and circumstances may dictate otherwise, it is preferred that water sample submissions be submitted to the Provincial Laboratory for Public Health (Microbiology), early within the week (Mondays, Tuesdays, Wednesdays) in order to avoid, as much as possible, the need for after hours, holiday and weekend emergency response reporting and the further necessity of courier or special delivery services.
B) Provincial Laboratory for Public Health (Microbiology)
• Within the hours 0800 - 1530, Monday to Friday, FAX all notifiable results to the local health agency.
• Outside of the hours of 0800 - 1530 and on statutory holidays and weekends PHONE the local health agency emergency contact and FAX all notifiable results to the local health agency.
• Notifiable results are defined as:
• The presence of one or more Total Coliform/E. coli per 100 mL
6.2.2 Follow-up Procedure and Intervention
The local health agency, upon being notified of a failed bacteriological result (see Chapter 3.1. for Result Interpretation) may initiate an emergency response
strategy based upon their determination of the degree of risk and according to their range of jurisdiction.
The health agency should attempt to notify the operator of a communal or public system directly within 24 hours of receiving the failed result. If contact by telephone is unsuccessful after 24 hours, a site visit should be considered.
Contact with the owner of a private system should also be attempted within 24 hours of receiving a notifiable result. However, indirect contact, such as providing the result and interpretation via telephone voice message, is
satisfactory. If telephone contact cannot be established with the home owner, the bacteriological report and interpretation should be mailed to the owner.
As a precaution, the operator/owner of a water supply with no treatment may be advised to boil drinking water, or use an alternate source in the interim, until further sampling can verify the result. In the case of a public or communal system, where the health of the public is at imminent risk, a Public Health Inspector should ideally inspect the water system and collect the sample for verification purposes within 24 hours following the initial notification.
Repeat Samples
In the event that repeat samples are required, the local health agency will verify that:
• In the case of a communal system, the system owner/operator has been instructed to collect and submit for analysis repeat samples that are upstream, downstream and at the same location as the site showing the contamination.
• In the case of a public system, the owner/operator has been instructed to collect and re-submit for analysis repeat sample(s) in numbers and locations as required by the Executive Officer.
• In the case of a private supply, the owner has been instructed to collect and submit for analysis repeat samples in numbers and at a location in accordance with the advice of the Executive Officer.
Note: Repeat samples must be clearly identified as such on the laboratory requisition form. When repeat samples are to be submitted, after hours or on weekends and holidays, the PLPH (M) must be notified in advance in order to
weekends the PLPH (M) will communicate all results of repeat samples to the local health agency by FAX and PHONE.
6.2.3 Public Health Intervention - Boil Water Order/Advisory
Boil Water Order: An Executive Officer may, in the case of a public or communal drinking water system, and where he/she deems it appropriate in the interest of safe guarding the publics’ health, issue a Boil Water Order pursuant to section 62 of the Public Health Act. It is the responsibility of the health agency to monitor and verify that the Boil Water Order has been implemented and followed to the satisfaction of the Executive Officer.
Note: A Boil Water Order is an Order issued by an Executive Officer pursuant to Section 62 of the Public Health Act. The Order may require the operator of a water system to advise consumers using that system (via posting, local media releases, door-to door canvassing, or whatever other measures the Executive Officer deems appropriate) that water used for drinking purposes must be boiled for a prescribed period of time prior to consumption. Boil Water Orders are intended as a temporary measure to allow remedial work on a drinking water system; they are not intended as an on-going method of treatment.
Note: The Health Agency should ensure that it maintains an updated contact list of high-risk groups using the water utility and that this list is contacted during a Boil Water Advisory (see Chapter 6.4.2).
Boil Water Advisory: As an alternative to a Boil Water Order, and where conditions or circumstances are deemed appropriate the Executive Officer may issue a Boil Water Advisory.
Note: A Boil Water Advisory is usually initiated for the same reasons as a Boil Water Order. It differs, however, in that it takes into consideration the limits of jurisdiction on privately owned facilities and, as such, is issued advising individuals that the water should not be used for drinking purposes unless it has been boiled for a prescribed period of time prior to consumption.
Note: Local health agencies will notify Alberta Health and Wellness, Environmental Health Strategies, during regular working hours of all Boil Water Orders or Advisories issued and rescinded in relationship to communal and public drinking water systems.
6.2.4 Rescinding a Boil Water Order/Advisory
The Boil Water Order/Advisory will be rescinded when the local health agency is satisfied that the conditions or concerns giving rise to the action have been satisfactorily remedied or otherwise addressed.
6.2.5 BOIL WATER ADVISORIES/ORDERS REPORT
Regional Health Authority:___________________________________
Community Effective Date
Reasons EHO/PHI
Name
Remedial Measures
Estimated Duration
New, Continued
Date Cancelled
(Lifted)
6.3 INFRASTRUCTURE FAILURE
Boil Water Advisory and No-Drinking Water Advisory Scenario:
The primary function for public health agencies during infrastructure failure is to ensure an adequate supply of water for essential function and protection of the public from exposures to pathogens and chemicals in the water supply.
Quantity of water available in emergencies is generally limited to meeting very basic survival needs of drinking, food preparation, and personal hygiene, and may not include bathing, showering, laundering or watering of plants and gardens. Water of unknown quality could be used to meet these non-priority water needs. Quality of emergency water is generally lower than that of the normal drinking water supply.
Priority in emergencies is to avoid immediate threats such as waterborne disease and dehydration. Other considerations such as short-term exposure to contaminants known to have lifetime exposure risks are discounted. Related priority is to provide an adequate supply of water for fire suppression.
There are basically four levels of responses by pubic health agencies during an infrastructure failure. These are dependent upon the severity and types of failure.
1. Failure to deliver adequate or safe water to a defined number of neighbourhoods or communities only i.e. limited disruption or loss of water
Example: Cross-connection and back-siphonage, sinkholes, leaking underground gasoline storage tanks and contaminated soil, main breaks and distribution line breakage, and power loss confined to certain sectors.
In this scenario, the basic infrastructure is still intact. While the delivery of safe water is restricted or interrupted, the primary function for public health agencies would be disease prevention and to work with utilities to allow a re-direction of water to the affected communities. Due to the proximity to other service lines or fire hydrants, emergency lines can be attached to provide temporary delivery of potable water.
Action Summary: cooperate with utility and municipality to ensure the delivery of an adequate supply of potable water
2. Failure to deliver adequate or safe supply of water to the whole community.
Example: Complete power failure, extreme weather conditions (hurricane, ice storms, flood, earthquake, tidal wave), terrorism, and chemical or biological contamination.
The primary function of the public health agency for total infrastructure failure is to find and deliver an adequate supply of water to essential services and for the whole community, and to set up a system to ensure the portability of the water used by the public for consumption.
In the failure to deliver an adequate or safe supply of water, there are potentially three scenarios:
2-A Microbial Contamination
Example: Presence of bacteria or protozoan in the water supply, or high turbidity indicating the increase risk or potential for microbial contamination.
Action Summary: Declare a Boil Water Advisory.
2-B Chemical Contamination
Example: The presence of toxic chemical(s) such as arsenic or blue-green algae toxins in the water supply. Boiling cannot render the water safe for consumption, and there may be a need to avoid skin (dermal) contact and reduce inhalation of vapours. Although the waste disposal system is still functional, wastewater treatment plants must be notified as to the cause as some toxic chemicals may affect the effectiveness of waste digestion. This is the most likely scenario for bio-terrorism.
Action Summary: Declare No-Drinking Water Advisory
2-C Total infrastructure failure
Example: Flooding or other natural disaster resulting in no water delivery to the whole community. Besides the concerns with the potability of water, there are also concerns with personal hygiene and waste disposal. Priority must be given to essential services.
Action Summary: Set up central stations for water delivery and waste disposal.
STEPS IN DECLARING A NO-DRINKING WATER ADVISORY
The basic responsibilities of public health agencies during infrastructure failure include:
1. Safe water delivery;
2. Waterborne disease prevention and outbreak detection; and 3. Other water-related issues during infrastructure failure.
I. SAFE WATER DELIVERY Objectives:
- Ensure a safe and adequate supply of water can be delivered to essential services such as emergency centres and hospitals
- Ensure an adequate supply of water can be delivered to the community (note: ideally, the water should be potable. However, there may be a potential for other
compounding factors that may make it necessary for the water to be further
disinfected prior to consumption. The primary goal should therefore be delivery of an adequate water supply, especially during complete infrastructure failure)
- Set up a testing protocol for the water to ensure safety of the water supply - Approve and inspect water haulers and water dispensing stations
- Provide information to the public on the safe receiving and storage of water
- Provide information to the public on the use of point-of-use devices, emergency water disinfection strategies or boil water protocols to ensure a safe supply of water
The delivery of adequate water during an infrastructure failure can be best achieved by proper emergency planning prior to the event. Public health agencies should be an integral part of a municipal emergency planning team, with representation at the control centre and representation on the media communication team.
During emergency planning for infrastructure failure, the following issues should be considered:
- Determine the availability of an alternate safe drinking water supply from neighbouring communities
- Assess the adequacy of the alternate drinking water supply and the safe delivery or transportation system
- Evaluate the functionality of the dispensing system
For severe events leading to complete infrastructure failure, the first 48 hours is usually the most chaotic and, in many cases, most critical for survival. There must be an adequate supply of water for emergency crews, essential food services, fire suppression, health care centers and other emergency services. Public health agencies should work closely with utilities to secure sufficient water for these uses.
Temporary water supplies that may be used include swimming pools, bottled water plants, packaged ice plants and water vending machines. These facilities or operations have basic water treatment devices on site and may have the storage capacity to provide potable water for a short period of time. Public health agencies may also want to consider
devices (see section 5.2). There are also commercial packaged water treatment plant companies in Canada and the US that can ship packaged units within 24-hours. These units can treat and provide temporary potable water for up to 100,000 individuals. If water is available through a well or spring, the source water must be fenced off, covered, and controlled. If possible, make immediate arrangements to store water and to distribute water at collection points away from the source to avoid direct contamination.
In general, the amount of water needed for displaced population is estimated as:
10 liters x no. of people x days = Liters/person/day (L/p/d) Feeding centers – 20-30 L/p/d
Health Care Centers – 40-60 L/p/d
Water can be distributed to individuals in a number of ways depending on local
conditions. Uncontrolled access by individual consumers to primary water sources must be avoided. A distribution system should have a sufficient number of taps or outlets relative to the size of the population to ensure that people do not wait for long periods to have access. Equity in the distribution of water is an extremely important consideration.
Ideally, no dwelling should be located further than 100 meters from a distribution point if the use of a vehicle is not possible.
As part of the emergency planning, information brochures such as the proper storage of water by homeowners during severe weather conditions should be prepared.
II. WATERBORNE DISEASE PREVENTION AND OUTBREAK MANAGEMENT Objectives:
- Prevent the outbreak of waterborne diseases;
- Prevent the outbreak of waterborne diseases;